Subcutaneous Immunotherapy for Mouse in Adults

The primary objective of the study is to assess if treatment with mouse subcutaneous
immunotherapy (SCIT), using the per protocol allergenic extract doses, is safe. This will be
done by determining the rate of related adverse events and serious adverse events in the
course of treatment.

Secondary objectives include:

- determination of whether a 24 week treatment with mouse SCIT, using the per protocol
allergenic extract doses, will induce a 3-fold increase in mouse-specific serum
immunoglobulin E (IgE)

- determination of whether a 24 week treatment with mouse SCIT, using the per protocol
allergenic extract doses, will induce changes in the serum levels of mouse-specific
immunoglobulin G (IgG) and immunoglobulin subclass 4 (IgG4).

INCLUSION CRITERIA

Participants who meet any of the following criteria are not eligible for enrollment but may
be reassessed. Participants are ineligible if they:

- Are pregnant or lactating. Females must be abstinent or use a medically acceptable
birth control method throughout the study (e.g. oral, subcutaneous, mechanical, or
surgical contraception);

- Cannot perform spirometry at Screening;

- Have an asthma severity classification at Recruitment of severe persistent, using the
NAEPP classification, as evidenced by at least one of the following:

- Requires a dose of greater than 500 mcg of fluticasone per day or the equivalent
of another inhaled corticosteroid;

- Have received more than 2 courses of oral or parenteral corticosteroids within
the last 12 months;

- Have been treated with depot steroids within the last 12 months;

- Have been hospitalized for asthma within the 6 months prior to recruitment;

- Have had a life-threatening asthma exacerbation that required intubation,
mechanical ventilation, or that resulted in a hypoxic seizure within 2 years
prior to recruitment.

- Do not have access to a phone (needed for scheduling appointments);

- Have received allergen immunotherapy (SLIT or SCIT) in the last 12 months prior to
recruitment or who plan to initiate or resume allergen immunotherapy during the study;

- Have previously been treated with anti-IgE therapy within 1 year of recruitment;

- Have received an investigational drug in the 30 days prior to recruitment or who plan
to use an investigational drug during the study;

- Refuses to sign the Epinephrine Auto-injector Training Form.

EXCLUSION CRITERIA

Participants who meet any of the following criteria are not eligible for enrollment and may
not be reassessed. Participants are ineligible if they:

- Do not primarily speak English;

- Plan to move from the area during the study period;

- Have a history of idiopathic anaphylaxis or anaphylaxis grade 2 or higher as defined
per protocol;

- Have unstable angina, significant arrhythmia, uncontrolled hypertension, history of
autoimmune disease, or other chronic or immunological diseases that in the opinion of
the investigator might interfere with the evaluation of the investigational agent or
pose additional risk to the participant;

- Are using tricyclic antidepressants or beta-adrenergic blocker drugs (both oral and
topical);

- Have not received the seasonal Flu (Influenza) Vaccine if enrolling December through
March.